#include <linux/fsnotify.h>
#include <linux/personality.h>
#include <linux/security.h>
+#include <linux/ima.h>
#include <linux/syscalls.h>
#include <linux/mount.h>
#include <linux/audit.h>
#include <linux/capability.h>
#include <linux/file.h>
#include <linux/fcntl.h>
-#include <asm/namei.h>
+#include <linux/device_cgroup.h>
+#include <linux/fs_struct.h>
#include <asm/uaccess.h>
#define ACC_MODE(x) ("\000\004\002\006"[(x)&O_ACCMODE])
* any extra contention...
*/
-static int link_path_walk(const char *name, struct nameidata *nd);
+static int __link_path_walk(const char *name, struct nameidata *nd);
/* In order to reduce some races, while at the same time doing additional
* checking and hopefully speeding things up, we copy filenames to the
{
umode_t mode = inode->i_mode;
- if (current->fsuid == inode->i_uid)
+ mask &= MAY_READ | MAY_WRITE | MAY_EXEC;
+
+ if (current_fsuid() == inode->i_uid)
mode >>= 6;
else {
if (IS_POSIXACL(inode) && (mode & S_IRWXG) && check_acl) {
/*
* If the DACs are ok we don't need any capability check.
*/
- if (((mode & mask & (MAY_READ|MAY_WRITE|MAY_EXEC)) == mask))
+ if ((mask & ~mode) == 0)
return 0;
check_capabilities:
* Read/write DACs are always overridable.
* Executable DACs are overridable if at least one exec bit is set.
*/
- if (!(mask & MAY_EXEC) ||
- (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode))
+ if (!(mask & MAY_EXEC) || execute_ok(inode))
if (capable(CAP_DAC_OVERRIDE))
return 0;
return -EACCES;
}
-int permission(struct inode *inode, int mask, struct nameidata *nd)
+/**
+ * inode_permission - check for access rights to a given inode
+ * @inode: inode to check permission on
+ * @mask: right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC)
+ *
+ * Used to check for read/write/execute permissions on an inode.
+ * We use "fsuid" for this, letting us set arbitrary permissions
+ * for filesystem access without changing the "normal" uids which
+ * are used for other things.
+ */
+int inode_permission(struct inode *inode, int mask)
{
- int retval, submask;
- struct vfsmount *mnt = NULL;
-
- if (nd)
- mnt = nd->path.mnt;
+ int retval;
if (mask & MAY_WRITE) {
umode_t mode = inode->i_mode;
return -EACCES;
}
- if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode)) {
- /*
- * MAY_EXEC on regular files is denied if the fs is mounted
- * with the "noexec" flag.
- */
- if (mnt && (mnt->mnt_flags & MNT_NOEXEC))
- return -EACCES;
- }
+ if (inode->i_op->permission)
+ retval = inode->i_op->permission(inode, mask);
+ else
+ retval = generic_permission(inode, mask, NULL);
- /* Ordinary permission routines do not understand MAY_APPEND. */
- submask = mask & ~MAY_APPEND;
- if (inode->i_op && inode->i_op->permission) {
- retval = inode->i_op->permission(inode, submask, nd);
- if (!retval) {
- /*
- * Exec permission on a regular file is denied if none
- * of the execute bits are set.
- *
- * This check should be done by the ->permission()
- * method.
- */
- if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode) &&
- !(inode->i_mode & S_IXUGO))
- return -EACCES;
- }
- } else {
- retval = generic_permission(inode, submask, NULL);
- }
if (retval)
return retval;
- return security_inode_permission(inode, mask, nd);
-}
+ retval = devcgroup_inode_permission(inode, mask);
+ if (retval)
+ return retval;
-/**
- * vfs_permission - check for access rights to a given path
- * @nd: lookup result that describes the path
- * @mask: right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC)
- *
- * Used to check for read/write/execute permissions on a path.
- * We use "fsuid" for this, letting us set arbitrary permissions
- * for filesystem access without changing the "normal" uids which
- * are used for other things.
- */
-int vfs_permission(struct nameidata *nd, int mask)
-{
- return permission(nd->path.dentry->d_inode, mask, nd);
+ return security_inode_permission(inode,
+ mask & (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND));
}
/**
*
* Note:
* Do not use this function in new code. All access checks should
- * be done using vfs_permission().
+ * be done using inode_permission().
*/
int file_permission(struct file *file, int mask)
{
- return permission(file->f_path.dentry->d_inode, mask, NULL);
+ return inode_permission(file->f_path.dentry->d_inode, mask);
}
/*
* short-cut DAC fails, then call permission() to do more
* complete permission check.
*/
-static int exec_permission_lite(struct inode *inode,
- struct nameidata *nd)
+static int exec_permission_lite(struct inode *inode)
{
umode_t mode = inode->i_mode;
- if (inode->i_op && inode->i_op->permission)
+ if (inode->i_op->permission)
return -EAGAIN;
- if (current->fsuid == inode->i_uid)
+ if (current_fsuid() == inode->i_uid)
mode >>= 6;
else if (in_group_p(inode->i_gid))
mode >>= 3;
return -EACCES;
ok:
- return security_inode_permission(inode, MAY_EXEC, nd);
+ return security_inode_permission(inode, MAY_EXEC);
}
/*
*/
result = d_lookup(parent, name);
if (!result) {
- struct dentry * dentry = d_alloc(parent, name);
+ struct dentry *dentry;
+
+ /* Don't create child dentry for a dead directory. */
+ result = ERR_PTR(-ENOENT);
+ if (IS_DEADDIR(dir))
+ goto out_unlock;
+
+ dentry = d_alloc(parent, name);
result = ERR_PTR(-ENOMEM);
if (dentry) {
result = dir->i_op->lookup(dir, dentry, nd);
else
result = dentry;
}
+out_unlock:
mutex_unlock(&dir->i_mutex);
return result;
}
return result;
}
-static int __emul_lookup_dentry(const char *, struct nameidata *);
-
-/* SMP-safe */
-static __always_inline int
-walk_init_root(const char *name, struct nameidata *nd)
+/*
+ * Wrapper to retry pathname resolution whenever the underlying
+ * file system returns an ESTALE.
+ *
+ * Retry the whole path once, forcing real lookup requests
+ * instead of relying on the dcache.
+ */
+static __always_inline int link_path_walk(const char *name, struct nameidata *nd)
{
- struct fs_struct *fs = current->fs;
+ struct path save = nd->path;
+ int result;
- read_lock(&fs->lock);
- if (fs->altroot && !(nd->flags & LOOKUP_NOALT)) {
- nd->path.mnt = mntget(fs->altrootmnt);
- nd->path.dentry = dget(fs->altroot);
- read_unlock(&fs->lock);
- if (__emul_lookup_dentry(name,nd))
- return 0;
+ /* make sure the stuff we saved doesn't go away */
+ path_get(&save);
+
+ result = __link_path_walk(name, nd);
+ if (result == -ESTALE) {
+ /* nd->path had been dropped */
+ nd->path = save;
+ path_get(&nd->path);
+ nd->flags |= LOOKUP_REVAL;
+ result = __link_path_walk(name, nd);
+ }
+
+ path_put(&save);
+
+ return result;
+}
+
+static __always_inline void set_root(struct nameidata *nd)
+{
+ if (!nd->root.mnt) {
+ struct fs_struct *fs = current->fs;
read_lock(&fs->lock);
+ nd->root = fs->root;
+ path_get(&nd->root);
+ read_unlock(&fs->lock);
}
- nd->path.mnt = mntget(fs->rootmnt);
- nd->path.dentry = dget(fs->root);
- read_unlock(&fs->lock);
- return 1;
}
static __always_inline int __vfs_follow_link(struct nameidata *nd, const char *link)
goto fail;
if (*link == '/') {
+ set_root(nd);
path_put(&nd->path);
- if (!walk_init_root(link, nd))
- /* weird __emul_prefix() stuff did it */
- goto out;
+ nd->path = nd->root;
+ path_get(&nd->root);
}
+
res = link_path_walk(link, nd);
-out:
if (nd->depth || res || nd->last_type!=LAST_NORM)
return res;
/*
static __always_inline void follow_dotdot(struct nameidata *nd)
{
- struct fs_struct *fs = current->fs;
+ set_root(nd);
while(1) {
struct vfsmount *parent;
struct dentry *old = nd->path.dentry;
- read_lock(&fs->lock);
- if (nd->path.dentry == fs->root &&
- nd->path.mnt == fs->rootmnt) {
- read_unlock(&fs->lock);
+ if (nd->path.dentry == nd->root.dentry &&
+ nd->path.mnt == nd->root.mnt) {
break;
}
- read_unlock(&fs->lock);
spin_lock(&dcache_lock);
if (nd->path.dentry != nd->path.mnt->mnt_root) {
nd->path.dentry = dget(nd->path.dentry->d_parent);
unsigned int c;
nd->flags |= LOOKUP_CONTINUE;
- err = exec_permission_lite(inode, nd);
+ err = exec_permission_lite(inode);
if (err == -EAGAIN)
- err = vfs_permission(nd, MAY_EXEC);
+ err = inode_permission(nd->path.dentry->d_inode,
+ MAY_EXEC);
+ if (!err)
+ err = ima_path_check(&nd->path, MAY_EXEC,
+ IMA_COUNT_UPDATE);
if (err)
break;
inode = next.dentry->d_inode;
if (!inode)
goto out_dput;
- err = -ENOTDIR;
- if (!inode->i_op)
- goto out_dput;
if (inode->i_op->follow_link) {
err = do_follow_link(&next, nd);
inode = nd->path.dentry->d_inode;
if (!inode)
break;
- err = -ENOTDIR;
- if (!inode->i_op)
- break;
} else
path_to_nameidata(&next, nd);
err = -ENOTDIR;
break;
inode = next.dentry->d_inode;
if ((lookup_flags & LOOKUP_FOLLOW)
- && inode && inode->i_op && inode->i_op->follow_link) {
+ && inode && inode->i_op->follow_link) {
err = do_follow_link(&next, nd);
if (err)
goto return_err;
break;
if (lookup_flags & LOOKUP_DIRECTORY) {
err = -ENOTDIR;
- if (!inode->i_op || !inode->i_op->lookup)
+ if (!inode->i_op->lookup)
break;
}
goto return_base;
return err;
}
-/*
- * Wrapper to retry pathname resolution whenever the underlying
- * file system returns an ESTALE.
- *
- * Retry the whole path once, forcing real lookup requests
- * instead of relying on the dcache.
- */
-static int link_path_walk(const char *name, struct nameidata *nd)
-{
- struct nameidata save = *nd;
- int result;
-
- /* make sure the stuff we saved doesn't go away */
- dget(save.path.dentry);
- mntget(save.path.mnt);
-
- result = __link_path_walk(name, nd);
- if (result == -ESTALE) {
- *nd = save;
- dget(nd->path.dentry);
- mntget(nd->path.mnt);
- nd->flags |= LOOKUP_REVAL;
- result = __link_path_walk(name, nd);
- }
-
- path_put(&save.path);
-
- return result;
-}
-
static int path_walk(const char *name, struct nameidata *nd)
{
current->total_link_count = 0;
return link_path_walk(name, nd);
}
-/*
- * SMP-safe: Returns 1 and nd will have valid dentry and mnt, if
- * everything is done. Returns 0 and drops input nd, if lookup failed;
- */
-static int __emul_lookup_dentry(const char *name, struct nameidata *nd)
-{
- if (path_walk(name, nd))
- return 0; /* something went wrong... */
-
- if (!nd->path.dentry->d_inode ||
- S_ISDIR(nd->path.dentry->d_inode->i_mode)) {
- struct path old_path = nd->path;
- struct qstr last = nd->last;
- int last_type = nd->last_type;
- struct fs_struct *fs = current->fs;
-
- /*
- * NAME was not found in alternate root or it's a directory.
- * Try to find it in the normal root:
- */
- nd->last_type = LAST_ROOT;
- read_lock(&fs->lock);
- nd->path.mnt = mntget(fs->rootmnt);
- nd->path.dentry = dget(fs->root);
- read_unlock(&fs->lock);
- if (path_walk(name, nd) == 0) {
- if (nd->path.dentry->d_inode) {
- path_put(&old_path);
- return 1;
- }
- path_put(&nd->path);
- }
- nd->path = old_path;
- nd->last = last;
- nd->last_type = last_type;
- }
- return 1;
-}
-
-void set_fs_altroot(void)
-{
- char *emul = __emul_prefix();
- struct nameidata nd;
- struct vfsmount *mnt = NULL, *oldmnt;
- struct dentry *dentry = NULL, *olddentry;
- int err;
- struct fs_struct *fs = current->fs;
-
- if (!emul)
- goto set_it;
- err = path_lookup(emul, LOOKUP_FOLLOW|LOOKUP_DIRECTORY|LOOKUP_NOALT, &nd);
- if (!err) {
- mnt = nd.path.mnt;
- dentry = nd.path.dentry;
- }
-set_it:
- write_lock(&fs->lock);
- oldmnt = fs->altrootmnt;
- olddentry = fs->altroot;
- fs->altrootmnt = mnt;
- fs->altroot = dentry;
- write_unlock(&fs->lock);
- if (olddentry) {
- dput(olddentry);
- mntput(oldmnt);
- }
-}
-
-/* Returns 0 and nd will be valid on success; Retuns error, otherwise. */
-static int do_path_lookup(int dfd, const char *name,
- unsigned int flags, struct nameidata *nd)
+static int path_init(int dfd, const char *name, unsigned int flags, struct nameidata *nd)
{
int retval = 0;
int fput_needed;
struct file *file;
- struct fs_struct *fs = current->fs;
nd->last_type = LAST_ROOT; /* if there are only slashes... */
nd->flags = flags;
nd->depth = 0;
+ nd->root.mnt = NULL;
if (*name=='/') {
- read_lock(&fs->lock);
- if (fs->altroot && !(nd->flags & LOOKUP_NOALT)) {
- nd->path.mnt = mntget(fs->altrootmnt);
- nd->path.dentry = dget(fs->altroot);
- read_unlock(&fs->lock);
- if (__emul_lookup_dentry(name,nd))
- goto out; /* found in altroot */
- read_lock(&fs->lock);
- }
- nd->path.mnt = mntget(fs->rootmnt);
- nd->path.dentry = dget(fs->root);
- read_unlock(&fs->lock);
+ set_root(nd);
+ nd->path = nd->root;
+ path_get(&nd->root);
} else if (dfd == AT_FDCWD) {
+ struct fs_struct *fs = current->fs;
read_lock(&fs->lock);
- nd->path.mnt = mntget(fs->pwdmnt);
- nd->path.dentry = dget(fs->pwd);
+ nd->path = fs->pwd;
+ path_get(&fs->pwd);
read_unlock(&fs->lock);
} else {
struct dentry *dentry;
fput_light(file, fput_needed);
}
+ return 0;
- retval = path_walk(name, nd);
-out:
+fput_fail:
+ fput_light(file, fput_needed);
+out_fail:
+ return retval;
+}
+
+/* Returns 0 and nd will be valid on success; Retuns error, otherwise. */
+static int do_path_lookup(int dfd, const char *name,
+ unsigned int flags, struct nameidata *nd)
+{
+ int retval = path_init(dfd, name, flags, nd);
+ if (!retval)
+ retval = path_walk(name, nd);
if (unlikely(!retval && !audit_dummy_context() && nd->path.dentry &&
nd->path.dentry->d_inode))
audit_inode(name, nd->path.dentry);
-out_fail:
+ if (nd->root.mnt) {
+ path_put(&nd->root);
+ nd->root.mnt = NULL;
+ }
return retval;
-
-fput_fail:
- fput_light(file, fput_needed);
- goto out_fail;
}
int path_lookup(const char *name, unsigned int flags,
return do_path_lookup(AT_FDCWD, name, flags, nd);
}
+int kern_path(const char *name, unsigned int flags, struct path *path)
+{
+ struct nameidata nd;
+ int res = do_path_lookup(AT_FDCWD, name, flags, &nd);
+ if (!res)
+ *path = nd.path;
+ return res;
+}
+
/**
* vfs_path_lookup - lookup a file path relative to a dentry-vfsmount pair
* @dentry: pointer to dentry of the base directory
nd->flags = flags;
nd->depth = 0;
- nd->path.mnt = mntget(mnt);
- nd->path.dentry = dget(dentry);
+ nd->path.dentry = dentry;
+ nd->path.mnt = mnt;
+ path_get(&nd->path);
+ nd->root = nd->path;
+ path_get(&nd->root);
retval = path_walk(name, nd);
if (unlikely(!retval && !audit_dummy_context() && nd->path.dentry &&
nd->path.dentry->d_inode))
audit_inode(name, nd->path.dentry);
- return retval;
+ path_put(&nd->root);
+ nd->root.mnt = NULL;
+ return retval;
}
-static int __path_lookup_intent_open(int dfd, const char *name,
- unsigned int lookup_flags, struct nameidata *nd,
- int open_flags, int create_mode)
+/**
+ * path_lookup_open - lookup a file path with open intent
+ * @dfd: the directory to use as base, or AT_FDCWD
+ * @name: pointer to file name
+ * @lookup_flags: lookup intent flags
+ * @nd: pointer to nameidata
+ * @open_flags: open intent flags
+ */
+static int path_lookup_open(int dfd, const char *name,
+ unsigned int lookup_flags, struct nameidata *nd, int open_flags)
{
struct file *filp = get_empty_filp();
int err;
return -ENFILE;
nd->intent.open.file = filp;
nd->intent.open.flags = open_flags;
- nd->intent.open.create_mode = create_mode;
+ nd->intent.open.create_mode = 0;
err = do_path_lookup(dfd, name, lookup_flags|LOOKUP_OPEN, nd);
if (IS_ERR(nd->intent.open.file)) {
if (err == 0) {
return err;
}
-/**
- * path_lookup_open - lookup a file path with open intent
- * @dfd: the directory to use as base, or AT_FDCWD
- * @name: pointer to file name
- * @lookup_flags: lookup intent flags
- * @nd: pointer to nameidata
- * @open_flags: open intent flags
- */
-int path_lookup_open(int dfd, const char *name, unsigned int lookup_flags,
- struct nameidata *nd, int open_flags)
-{
- return __path_lookup_intent_open(dfd, name, lookup_flags, nd,
- open_flags, 0);
-}
-
-/**
- * path_lookup_create - lookup a file path with open + create intent
- * @dfd: the directory to use as base, or AT_FDCWD
- * @name: pointer to file name
- * @lookup_flags: lookup intent flags
- * @nd: pointer to nameidata
- * @open_flags: open intent flags
- * @create_mode: create intent flags
- */
-static int path_lookup_create(int dfd, const char *name,
- unsigned int lookup_flags, struct nameidata *nd,
- int open_flags, int create_mode)
-{
- return __path_lookup_intent_open(dfd, name, lookup_flags|LOOKUP_CREATE,
- nd, open_flags, create_mode);
-}
-
-int __user_path_lookup_open(const char __user *name, unsigned int lookup_flags,
- struct nameidata *nd, int open_flags)
-{
- char *tmp = getname(name);
- int err = PTR_ERR(tmp);
-
- if (!IS_ERR(tmp)) {
- err = __path_lookup_intent_open(AT_FDCWD, tmp, lookup_flags, nd, open_flags, 0);
- putname(tmp);
- }
- return err;
-}
-
static struct dentry *__lookup_hash(struct qstr *name,
struct dentry *base, struct nameidata *nd)
{
dentry = cached_lookup(base, name, nd);
if (!dentry) {
- struct dentry *new = d_alloc(base, name);
+ struct dentry *new;
+
+ /* Don't create child dentry for a dead directory. */
+ dentry = ERR_PTR(-ENOENT);
+ if (IS_DEADDIR(inode))
+ goto out;
+
+ new = d_alloc(base, name);
dentry = ERR_PTR(-ENOMEM);
if (!new)
goto out;
{
int err;
- err = permission(nd->path.dentry->d_inode, MAY_EXEC, nd);
+ err = inode_permission(nd->path.dentry->d_inode, MAY_EXEC);
if (err)
return ERR_PTR(err);
return __lookup_hash(&nd->last, nd->path.dentry, nd);
}
/**
- * lookup_one_len: filesystem helper to lookup single pathname component
+ * lookup_one_len - filesystem helper to lookup single pathname component
* @name: pathname component to lookup
* @base: base directory to lookup from
* @len: maximum length @len should be interpreted to
*
- * Note that this routine is purely a helper for filesystem useage and should
- * not be called by generic code. Also note that by using this function to
+ * Note that this routine is purely a helper for filesystem usage and should
+ * not be called by generic code. Also note that by using this function the
* nameidata argument is passed to the filesystem methods and a filesystem
* using this helper needs to be prepared for that.
*/
int err;
struct qstr this;
+ WARN_ON_ONCE(!mutex_is_locked(&base->d_inode->i_mutex));
+
err = __lookup_one_len(name, &this, base, len);
if (err)
return ERR_PTR(err);
- err = permission(base->d_inode, MAY_EXEC, NULL);
+ err = inode_permission(base->d_inode, MAY_EXEC);
if (err)
return ERR_PTR(err);
return __lookup_hash(&this, base, NULL);
return __lookup_hash(&this, base, NULL);
}
-int __user_walk_fd(int dfd, const char __user *name, unsigned flags,
- struct nameidata *nd)
+int user_path_at(int dfd, const char __user *name, unsigned flags,
+ struct path *path)
{
+ struct nameidata nd;
char *tmp = getname(name);
int err = PTR_ERR(tmp);
-
if (!IS_ERR(tmp)) {
- err = do_path_lookup(dfd, tmp, flags, nd);
+
+ BUG_ON(flags & LOOKUP_PARENT);
+
+ err = do_path_lookup(dfd, tmp, flags, &nd);
putname(tmp);
+ if (!err)
+ *path = nd.path;
}
return err;
}
-int __user_walk(const char __user *name, unsigned flags, struct nameidata *nd)
+static int user_path_parent(int dfd, const char __user *path,
+ struct nameidata *nd, char **name)
{
- return __user_walk_fd(AT_FDCWD, name, flags, nd);
+ char *s = getname(path);
+ int error;
+
+ if (IS_ERR(s))
+ return PTR_ERR(s);
+
+ error = do_path_lookup(dfd, s, LOOKUP_PARENT, nd);
+ if (error)
+ putname(s);
+ else
+ *name = s;
+
+ return error;
}
/*
*/
static inline int check_sticky(struct inode *dir, struct inode *inode)
{
+ uid_t fsuid = current_fsuid();
+
if (!(dir->i_mode & S_ISVTX))
return 0;
- if (inode->i_uid == current->fsuid)
+ if (inode->i_uid == fsuid)
return 0;
- if (dir->i_uid == current->fsuid)
+ if (dir->i_uid == fsuid)
return 0;
return !capable(CAP_FOWNER);
}
BUG_ON(victim->d_parent->d_inode != dir);
audit_inode_child(victim->d_name.name, victim, dir);
- error = permission(dir,MAY_WRITE | MAY_EXEC, NULL);
+ error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
if (error)
return error;
if (IS_APPEND(dir))
return -EPERM;
if (check_sticky(dir, victim->d_inode)||IS_APPEND(victim->d_inode)||
- IS_IMMUTABLE(victim->d_inode))
+ IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
return -EPERM;
if (isdir) {
if (!S_ISDIR(victim->d_inode->i_mode))
* 3. We should have write and exec permissions on dir
* 4. We can't do it if dir is immutable (done in permission())
*/
-static inline int may_create(struct inode *dir, struct dentry *child,
- struct nameidata *nd)
+static inline int may_create(struct inode *dir, struct dentry *child)
{
if (child->d_inode)
return -EEXIST;
if (IS_DEADDIR(dir))
return -ENOENT;
- return permission(dir,MAY_WRITE | MAY_EXEC, nd);
+ return inode_permission(dir, MAY_WRITE | MAY_EXEC);
}
/*
mutex_lock(&p1->d_inode->i_sb->s_vfs_rename_mutex);
- for (p = p1; p->d_parent != p; p = p->d_parent) {
- if (p->d_parent == p2) {
- mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_PARENT);
- mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_CHILD);
- return p;
- }
+ p = d_ancestor(p2, p1);
+ if (p) {
+ mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_PARENT);
+ mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_CHILD);
+ return p;
}
- for (p = p2; p->d_parent != p; p = p->d_parent) {
- if (p->d_parent == p1) {
- mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT);
- mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_CHILD);
- return p;
- }
+ p = d_ancestor(p1, p2);
+ if (p) {
+ mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT);
+ mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_CHILD);
+ return p;
}
mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT);
int vfs_create(struct inode *dir, struct dentry *dentry, int mode,
struct nameidata *nd)
{
- int error = may_create(dir, dentry, nd);
+ int error = may_create(dir, dentry);
if (error)
return error;
- if (!dir->i_op || !dir->i_op->create)
+ if (!dir->i_op->create)
return -EACCES; /* shouldn't it be ENOSYS? */
mode &= S_IALLUGO;
mode |= S_IFREG;
error = security_inode_create(dir, dentry, mode);
if (error)
return error;
- DQUOT_INIT(dir);
+ vfs_dq_init(dir);
error = dir->i_op->create(dir, dentry, mode, nd);
if (!error)
fsnotify_create(dir, dentry);
return error;
}
-int may_open(struct nameidata *nd, int acc_mode, int flag)
+int may_open(struct path *path, int acc_mode, int flag)
{
- struct dentry *dentry = nd->path.dentry;
+ struct dentry *dentry = path->dentry;
struct inode *inode = dentry->d_inode;
int error;
if (!inode)
return -ENOENT;
- if (S_ISLNK(inode->i_mode))
+ switch (inode->i_mode & S_IFMT) {
+ case S_IFLNK:
return -ELOOP;
-
- if (S_ISDIR(inode->i_mode) && (acc_mode & MAY_WRITE))
- return -EISDIR;
-
- /*
- * FIFO's, sockets and device files are special: they don't
- * actually live on the filesystem itself, and as such you
- * can write to them even if the filesystem is read-only.
- */
- if (S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
- flag &= ~O_TRUNC;
- } else if (S_ISBLK(inode->i_mode) || S_ISCHR(inode->i_mode)) {
- if (nd->path.mnt->mnt_flags & MNT_NODEV)
+ case S_IFDIR:
+ if (acc_mode & MAY_WRITE)
+ return -EISDIR;
+ break;
+ case S_IFBLK:
+ case S_IFCHR:
+ if (path->mnt->mnt_flags & MNT_NODEV)
return -EACCES;
-
+ /*FALLTHRU*/
+ case S_IFIFO:
+ case S_IFSOCK:
flag &= ~O_TRUNC;
- } else if (IS_RDONLY(inode) && (acc_mode & MAY_WRITE))
- return -EROFS;
+ break;
+ }
+
+ error = inode_permission(inode, acc_mode);
+ if (error)
+ return error;
- error = vfs_permission(nd, acc_mode);
+ error = ima_path_check(path,
+ acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC),
+ IMA_COUNT_UPDATE);
if (error)
return error;
/*
* Refuse to truncate files with mandatory locks held on them.
*/
error = locks_verify_locked(inode);
+ if (!error)
+ error = security_path_truncate(path, 0,
+ ATTR_MTIME|ATTR_CTIME|ATTR_OPEN);
if (!error) {
- DQUOT_INIT(inode);
+ vfs_dq_init(inode);
error = do_truncate(dentry, 0,
ATTR_MTIME|ATTR_CTIME|ATTR_OPEN,
return error;
} else
if (flag & FMODE_WRITE)
- DQUOT_INIT(inode);
+ vfs_dq_init(inode);
return 0;
}
-static int open_namei_create(struct nameidata *nd, struct path *path,
+/*
+ * Be careful about ever adding any more callers of this
+ * function. Its flags must be in the namei format, not
+ * what get passed to sys_open().
+ */
+static int __open_namei_create(struct nameidata *nd, struct path *path,
int flag, int mode)
{
int error;
struct dentry *dir = nd->path.dentry;
if (!IS_POSIXACL(dir->d_inode))
- mode &= ~current->fs->umask;
+ mode &= ~current_umask();
+ error = security_path_mknod(&nd->path, path->dentry, mode, 0);
+ if (error)
+ goto out_unlock;
error = vfs_create(dir->d_inode, path->dentry, mode, nd);
+out_unlock:
mutex_unlock(&dir->d_inode->i_mutex);
dput(nd->path.dentry);
nd->path.dentry = path->dentry;
if (error)
return error;
/* Don't check for write permission, don't truncate */
- return may_open(nd, 0, flag & ~O_TRUNC);
+ return may_open(&nd->path, 0, flag & ~O_TRUNC);
}
/*
- * open_namei()
- *
- * namei for open - this is in fact almost the whole open-routine.
+ * Note that while the flag value (low two bits) for sys_open means:
+ * 00 - read-only
+ * 01 - write-only
+ * 10 - read-write
+ * 11 - special
+ * it is changed into
+ * 00 - no permissions needed
+ * 01 - read-permission
+ * 10 - write-permission
+ * 11 - read-write
+ * for the internal routines (ie open_namei()/follow_link() etc)
+ * This is more logical, and also allows the 00 "no perm needed"
+ * to be used for symlinks (where the permissions are checked
+ * later).
*
- * Note that the low bits of "flag" aren't the same as in the open
- * system call - they are 00 - no permissions needed
- * 01 - read permission needed
- * 10 - write permission needed
- * 11 - read/write permissions needed
- * which is a lot more logical, and also allows the "no perm" needed
- * for symlinks (where the permissions are checked later).
- * SMP-safe
+*/
+static inline int open_to_namei_flags(int flag)
+{
+ if ((flag+1) & O_ACCMODE)
+ flag++;
+ return flag;
+}
+
+static int open_will_write_to_fs(int flag, struct inode *inode)
+{
+ /*
+ * We'll never write to the fs underlying
+ * a device file.
+ */
+ if (special_file(inode->i_mode))
+ return 0;
+ return (flag & O_TRUNC);
+}
+
+/*
+ * Note that the low bits of the passed in "open_flag"
+ * are not the same as in the local variable "flag". See
+ * open_to_namei_flags() for more details.
*/
-int open_namei(int dfd, const char *pathname, int flag,
- int mode, struct nameidata *nd)
+struct file *do_filp_open(int dfd, const char *pathname,
+ int open_flag, int mode, int acc_mode)
{
- int acc_mode, error;
+ struct file *filp;
+ struct nameidata nd;
+ int error;
struct path path;
struct dentry *dir;
int count = 0;
+ int will_write;
+ int flag = open_to_namei_flags(open_flag);
- acc_mode = ACC_MODE(flag);
+ if (!acc_mode)
+ acc_mode = MAY_OPEN | ACC_MODE(flag);
/* O_TRUNC implies we need access checks for write permissions */
if (flag & O_TRUNC)
*/
if (!(flag & O_CREAT)) {
error = path_lookup_open(dfd, pathname, lookup_flags(flag),
- nd, flag);
+ &nd, flag);
if (error)
- return error;
+ return ERR_PTR(error);
goto ok;
}
/*
* Create - we need to know the parent.
*/
- error = path_lookup_create(dfd,pathname,LOOKUP_PARENT,nd,flag,mode);
+ error = path_init(dfd, pathname, LOOKUP_PARENT, &nd);
if (error)
- return error;
+ return ERR_PTR(error);
+ error = path_walk(pathname, &nd);
+ if (error)
+ return ERR_PTR(error);
+ if (unlikely(!audit_dummy_context()))
+ audit_inode(pathname, nd.path.dentry);
/*
* We have the parent and last component. First of all, check
* will not do.
*/
error = -EISDIR;
- if (nd->last_type != LAST_NORM || nd->last.name[nd->last.len])
- goto exit;
+ if (nd.last_type != LAST_NORM || nd.last.name[nd.last.len])
+ goto exit_parent;
- dir = nd->path.dentry;
- nd->flags &= ~LOOKUP_PARENT;
+ error = -ENFILE;
+ filp = get_empty_filp();
+ if (filp == NULL)
+ goto exit_parent;
+ nd.intent.open.file = filp;
+ nd.intent.open.flags = flag;
+ nd.intent.open.create_mode = mode;
+ dir = nd.path.dentry;
+ nd.flags &= ~LOOKUP_PARENT;
+ nd.flags |= LOOKUP_CREATE | LOOKUP_OPEN;
+ if (flag & O_EXCL)
+ nd.flags |= LOOKUP_EXCL;
mutex_lock(&dir->d_inode->i_mutex);
- path.dentry = lookup_hash(nd);
- path.mnt = nd->path.mnt;
+ path.dentry = lookup_hash(&nd);
+ path.mnt = nd.path.mnt;
do_last:
error = PTR_ERR(path.dentry);
goto exit;
}
- if (IS_ERR(nd->intent.open.file)) {
- mutex_unlock(&dir->d_inode->i_mutex);
- error = PTR_ERR(nd->intent.open.file);
- goto exit_dput;
+ if (IS_ERR(nd.intent.open.file)) {
+ error = PTR_ERR(nd.intent.open.file);
+ goto exit_mutex_unlock;
}
/* Negative dentry, just create the file */
if (!path.dentry->d_inode) {
- error = open_namei_create(nd, &path, flag, mode);
+ /*
+ * This write is needed to ensure that a
+ * ro->rw transition does not occur between
+ * the time when the file is created and when
+ * a permanent write count is taken through
+ * the 'struct file' in nameidata_to_filp().
+ */
+ error = mnt_want_write(nd.path.mnt);
if (error)
+ goto exit_mutex_unlock;
+ error = __open_namei_create(&nd, &path, flag, mode);
+ if (error) {
+ mnt_drop_write(nd.path.mnt);
goto exit;
- return 0;
+ }
+ filp = nameidata_to_filp(&nd, open_flag);
+ mnt_drop_write(nd.path.mnt);
+ return filp;
}
/*
error = -ENOENT;
if (!path.dentry->d_inode)
goto exit_dput;
- if (path.dentry->d_inode->i_op && path.dentry->d_inode->i_op->follow_link)
+ if (path.dentry->d_inode->i_op->follow_link)
goto do_link;
- path_to_nameidata(&path, nd);
+ path_to_nameidata(&path, &nd);
error = -EISDIR;
if (path.dentry->d_inode && S_ISDIR(path.dentry->d_inode->i_mode))
goto exit;
ok:
- error = may_open(nd, acc_mode, flag);
- if (error)
+ /*
+ * Consider:
+ * 1. may_open() truncates a file
+ * 2. a rw->ro mount transition occurs
+ * 3. nameidata_to_filp() fails due to
+ * the ro mount.
+ * That would be inconsistent, and should
+ * be avoided. Taking this mnt write here
+ * ensures that (2) can not occur.
+ */
+ will_write = open_will_write_to_fs(flag, nd.path.dentry->d_inode);
+ if (will_write) {
+ error = mnt_want_write(nd.path.mnt);
+ if (error)
+ goto exit;
+ }
+ error = may_open(&nd.path, acc_mode, flag);
+ if (error) {
+ if (will_write)
+ mnt_drop_write(nd.path.mnt);
goto exit;
- return 0;
+ }
+ filp = nameidata_to_filp(&nd, open_flag);
+ /*
+ * It is now safe to drop the mnt write
+ * because the filp has had a write taken
+ * on its behalf.
+ */
+ if (will_write)
+ mnt_drop_write(nd.path.mnt);
+ return filp;
+exit_mutex_unlock:
+ mutex_unlock(&dir->d_inode->i_mutex);
exit_dput:
- path_put_conditional(&path, nd);
+ path_put_conditional(&path, &nd);
exit:
- if (!IS_ERR(nd->intent.open.file))
- release_open_intent(nd);
- path_put(&nd->path);
- return error;
+ if (!IS_ERR(nd.intent.open.file))
+ release_open_intent(&nd);
+exit_parent:
+ if (nd.root.mnt)
+ path_put(&nd.root);
+ path_put(&nd.path);
+ return ERR_PTR(error);
do_link:
error = -ELOOP;
* stored in nd->last.name and we will have to putname() it when we
* are done. Procfs-like symlinks just set LAST_BIND.
*/
- nd->flags |= LOOKUP_PARENT;
- error = security_inode_follow_link(path.dentry, nd);
+ nd.flags |= LOOKUP_PARENT;
+ error = security_inode_follow_link(path.dentry, &nd);
if (error)
goto exit_dput;
- error = __do_follow_link(&path, nd);
+ error = __do_follow_link(&path, &nd);
if (error) {
/* Does someone understand code flow here? Or it is only
* me so stupid? Anathema to whoever designed this non-sense
* with "intent.open".
*/
- release_open_intent(nd);
- return error;
+ release_open_intent(&nd);
+ return ERR_PTR(error);
}
- nd->flags &= ~LOOKUP_PARENT;
- if (nd->last_type == LAST_BIND)
+ nd.flags &= ~LOOKUP_PARENT;
+ if (nd.last_type == LAST_BIND)
goto ok;
error = -EISDIR;
- if (nd->last_type != LAST_NORM)
+ if (nd.last_type != LAST_NORM)
goto exit;
- if (nd->last.name[nd->last.len]) {
- __putname(nd->last.name);
+ if (nd.last.name[nd.last.len]) {
+ __putname(nd.last.name);
goto exit;
}
error = -ELOOP;
if (count++==32) {
- __putname(nd->last.name);
+ __putname(nd.last.name);
goto exit;
}
- dir = nd->path.dentry;
+ dir = nd.path.dentry;
mutex_lock(&dir->d_inode->i_mutex);
- path.dentry = lookup_hash(nd);
- path.mnt = nd->path.mnt;
- __putname(nd->last.name);
+ path.dentry = lookup_hash(&nd);
+ path.mnt = nd.path.mnt;
+ __putname(nd.last.name);
goto do_last;
}
+/**
+ * filp_open - open file and return file pointer
+ *
+ * @filename: path to open
+ * @flags: open flags as per the open(2) second argument
+ * @mode: mode for the new file if O_CREAT is set, else ignored
+ *
+ * This is the helper to open a file from kernelspace if you really
+ * have to. But in generally you should not do this, so please move
+ * along, nothing to see here..
+ */
+struct file *filp_open(const char *filename, int flags, int mode)
+{
+ return do_filp_open(AT_FDCWD, filename, flags, mode, 0);
+}
+EXPORT_SYMBOL(filp_open);
+
/**
* lookup_create - lookup a dentry, creating it if it doesn't exist
* @nd: nameidata info
if (nd->last_type != LAST_NORM)
goto fail;
nd->flags &= ~LOOKUP_PARENT;
- nd->flags |= LOOKUP_CREATE;
+ nd->flags |= LOOKUP_CREATE | LOOKUP_EXCL;
nd->intent.open.flags = O_EXCL;
/*
if (IS_ERR(dentry))
goto fail;
+ if (dentry->d_inode)
+ goto eexist;
/*
* Special case - lookup gave negative, but... we had foo/bar/
* From the vfs_mknod() POV we just have a negative dentry -
* all is fine. Let's be bastards - you had / on the end, you've
* been asking for (non-existent) directory. -ENOENT for you.
*/
- if (!is_dir && nd->last.name[nd->last.len] && !dentry->d_inode)
- goto enoent;
+ if (unlikely(!is_dir && nd->last.name[nd->last.len])) {
+ dput(dentry);
+ dentry = ERR_PTR(-ENOENT);
+ }
return dentry;
-enoent:
+eexist:
dput(dentry);
- dentry = ERR_PTR(-ENOENT);
+ dentry = ERR_PTR(-EEXIST);
fail:
return dentry;
}
int vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
{
- int error = may_create(dir, dentry, NULL);
+ int error = may_create(dir, dentry);
if (error)
return error;
if ((S_ISCHR(mode) || S_ISBLK(mode)) && !capable(CAP_MKNOD))
return -EPERM;
- if (!dir->i_op || !dir->i_op->mknod)
+ if (!dir->i_op->mknod)
return -EPERM;
+ error = devcgroup_inode_mknod(mode, dev);
+ if (error)
+ return error;
+
error = security_inode_mknod(dir, dentry, mode, dev);
if (error)
return error;
- DQUOT_INIT(dir);
+ vfs_dq_init(dir);
error = dir->i_op->mknod(dir, dentry, mode, dev);
if (!error)
fsnotify_create(dir, dentry);
return error;
}
-asmlinkage long sys_mknodat(int dfd, const char __user *filename, int mode,
- unsigned dev)
+static int may_mknod(mode_t mode)
{
- int error = 0;
- char * tmp;
- struct dentry * dentry;
+ switch (mode & S_IFMT) {
+ case S_IFREG:
+ case S_IFCHR:
+ case S_IFBLK:
+ case S_IFIFO:
+ case S_IFSOCK:
+ case 0: /* zero mode translates to S_IFREG */
+ return 0;
+ case S_IFDIR:
+ return -EPERM;
+ default:
+ return -EINVAL;
+ }
+}
+
+SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, int, mode,
+ unsigned, dev)
+{
+ int error;
+ char *tmp;
+ struct dentry *dentry;
struct nameidata nd;
if (S_ISDIR(mode))
return -EPERM;
- tmp = getname(filename);
- if (IS_ERR(tmp))
- return PTR_ERR(tmp);
- error = do_path_lookup(dfd, tmp, LOOKUP_PARENT, &nd);
+ error = user_path_parent(dfd, filename, &nd, &tmp);
if (error)
- goto out;
- dentry = lookup_create(&nd, 0);
- error = PTR_ERR(dentry);
+ return error;
+ dentry = lookup_create(&nd, 0);
+ if (IS_ERR(dentry)) {
+ error = PTR_ERR(dentry);
+ goto out_unlock;
+ }
if (!IS_POSIXACL(nd.path.dentry->d_inode))
- mode &= ~current->fs->umask;
- if (!IS_ERR(dentry)) {
- switch (mode & S_IFMT) {
+ mode &= ~current_umask();
+ error = may_mknod(mode);
+ if (error)
+ goto out_dput;
+ error = mnt_want_write(nd.path.mnt);
+ if (error)
+ goto out_dput;
+ error = security_path_mknod(&nd.path, dentry, mode, dev);
+ if (error)
+ goto out_drop_write;
+ switch (mode & S_IFMT) {
case 0: case S_IFREG:
error = vfs_create(nd.path.dentry->d_inode,dentry,mode,&nd);
break;
case S_IFIFO: case S_IFSOCK:
error = vfs_mknod(nd.path.dentry->d_inode,dentry,mode,0);
break;
- case S_IFDIR:
- error = -EPERM;
- break;
- default:
- error = -EINVAL;
- }
- dput(dentry);
}
+out_drop_write:
+ mnt_drop_write(nd.path.mnt);
+out_dput:
+ dput(dentry);
+out_unlock:
mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
path_put(&nd.path);
-out:
putname(tmp);
return error;
}
-asmlinkage long sys_mknod(const char __user *filename, int mode, unsigned dev)
+SYSCALL_DEFINE3(mknod, const char __user *, filename, int, mode, unsigned, dev)
{
return sys_mknodat(AT_FDCWD, filename, mode, dev);
}
int vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
{
- int error = may_create(dir, dentry, NULL);
+ int error = may_create(dir, dentry);
if (error)
return error;
- if (!dir->i_op || !dir->i_op->mkdir)
+ if (!dir->i_op->mkdir)
return -EPERM;
mode &= (S_IRWXUGO|S_ISVTX);
if (error)
return error;
- DQUOT_INIT(dir);
+ vfs_dq_init(dir);
error = dir->i_op->mkdir(dir, dentry, mode);
if (!error)
fsnotify_mkdir(dir, dentry);
return error;
}
-asmlinkage long sys_mkdirat(int dfd, const char __user *pathname, int mode)
+SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, int, mode)
{
int error = 0;
char * tmp;
struct dentry *dentry;
struct nameidata nd;
- tmp = getname(pathname);
- error = PTR_ERR(tmp);
- if (IS_ERR(tmp))
+ error = user_path_parent(dfd, pathname, &nd, &tmp);
+ if (error)
goto out_err;
- error = do_path_lookup(dfd, tmp, LOOKUP_PARENT, &nd);
- if (error)
- goto out;
dentry = lookup_create(&nd, 1);
error = PTR_ERR(dentry);
if (IS_ERR(dentry))
goto out_unlock;
if (!IS_POSIXACL(nd.path.dentry->d_inode))
- mode &= ~current->fs->umask;
+ mode &= ~current_umask();
+ error = mnt_want_write(nd.path.mnt);
+ if (error)
+ goto out_dput;
+ error = security_path_mkdir(&nd.path, dentry, mode);
+ if (error)
+ goto out_drop_write;
error = vfs_mkdir(nd.path.dentry->d_inode, dentry, mode);
+out_drop_write:
+ mnt_drop_write(nd.path.mnt);
+out_dput:
dput(dentry);
out_unlock:
mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
path_put(&nd.path);
-out:
putname(tmp);
out_err:
return error;
}
-asmlinkage long sys_mkdir(const char __user *pathname, int mode)
+SYSCALL_DEFINE2(mkdir, const char __user *, pathname, int, mode)
{
return sys_mkdirat(AT_FDCWD, pathname, mode);
}
if (error)
return error;
- if (!dir->i_op || !dir->i_op->rmdir)
+ if (!dir->i_op->rmdir)
return -EPERM;
- DQUOT_INIT(dir);
+ vfs_dq_init(dir);
mutex_lock(&dentry->d_inode->i_mutex);
dentry_unhash(dentry);
struct dentry *dentry;
struct nameidata nd;
- name = getname(pathname);
- if(IS_ERR(name))
- return PTR_ERR(name);
-
- error = do_path_lookup(dfd, name, LOOKUP_PARENT, &nd);
+ error = user_path_parent(dfd, pathname, &nd, &name);
if (error)
- goto exit;
+ return error;
switch(nd.last_type) {
- case LAST_DOTDOT:
- error = -ENOTEMPTY;
- goto exit1;
- case LAST_DOT:
- error = -EINVAL;
- goto exit1;
- case LAST_ROOT:
- error = -EBUSY;
- goto exit1;
+ case LAST_DOTDOT:
+ error = -ENOTEMPTY;
+ goto exit1;
+ case LAST_DOT:
+ error = -EINVAL;
+ goto exit1;
+ case LAST_ROOT:
+ error = -EBUSY;
+ goto exit1;
}
+
+ nd.flags &= ~LOOKUP_PARENT;
+
mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
dentry = lookup_hash(&nd);
error = PTR_ERR(dentry);
if (IS_ERR(dentry))
goto exit2;
+ error = mnt_want_write(nd.path.mnt);
+ if (error)
+ goto exit3;
+ error = security_path_rmdir(&nd.path, dentry);
+ if (error)
+ goto exit4;
error = vfs_rmdir(nd.path.dentry->d_inode, dentry);
+exit4:
+ mnt_drop_write(nd.path.mnt);
+exit3:
dput(dentry);
exit2:
mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
exit1:
path_put(&nd.path);
-exit:
putname(name);
return error;
}
-asmlinkage long sys_rmdir(const char __user *pathname)
+SYSCALL_DEFINE1(rmdir, const char __user *, pathname)
{
return do_rmdir(AT_FDCWD, pathname);
}
if (error)
return error;
- if (!dir->i_op || !dir->i_op->unlink)
+ if (!dir->i_op->unlink)
return -EPERM;
- DQUOT_INIT(dir);
+ vfs_dq_init(dir);
mutex_lock(&dentry->d_inode->i_mutex);
if (d_mountpoint(dentry))
*/
static long do_unlinkat(int dfd, const char __user *pathname)
{
- int error = 0;
- char * name;
+ int error;
+ char *name;
struct dentry *dentry;
struct nameidata nd;
struct inode *inode = NULL;
- name = getname(pathname);
- if(IS_ERR(name))
- return PTR_ERR(name);
-
- error = do_path_lookup(dfd, name, LOOKUP_PARENT, &nd);
+ error = user_path_parent(dfd, pathname, &nd, &name);
if (error)
- goto exit;
+ return error;
+
error = -EISDIR;
if (nd.last_type != LAST_NORM)
goto exit1;
+
+ nd.flags &= ~LOOKUP_PARENT;
+
mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
dentry = lookup_hash(&nd);
error = PTR_ERR(dentry);
inode = dentry->d_inode;
if (inode)
atomic_inc(&inode->i_count);
+ error = mnt_want_write(nd.path.mnt);
+ if (error)
+ goto exit2;
+ error = security_path_unlink(&nd.path, dentry);
+ if (error)
+ goto exit3;
error = vfs_unlink(nd.path.dentry->d_inode, dentry);
+exit3:
+ mnt_drop_write(nd.path.mnt);
exit2:
dput(dentry);
}
iput(inode); /* truncate the inode here */
exit1:
path_put(&nd.path);
-exit:
putname(name);
return error;
goto exit2;
}
-asmlinkage long sys_unlinkat(int dfd, const char __user *pathname, int flag)
+SYSCALL_DEFINE3(unlinkat, int, dfd, const char __user *, pathname, int, flag)
{
if ((flag & ~AT_REMOVEDIR) != 0)
return -EINVAL;
return do_unlinkat(dfd, pathname);
}
-asmlinkage long sys_unlink(const char __user *pathname)
+SYSCALL_DEFINE1(unlink, const char __user *, pathname)
{
return do_unlinkat(AT_FDCWD, pathname);
}
-int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname, int mode)
+int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname)
{
- int error = may_create(dir, dentry, NULL);
+ int error = may_create(dir, dentry);
if (error)
return error;
- if (!dir->i_op || !dir->i_op->symlink)
+ if (!dir->i_op->symlink)
return -EPERM;
error = security_inode_symlink(dir, dentry, oldname);
if (error)
return error;
- DQUOT_INIT(dir);
+ vfs_dq_init(dir);
error = dir->i_op->symlink(dir, dentry, oldname);
if (!error)
fsnotify_create(dir, dentry);
return error;
}
-asmlinkage long sys_symlinkat(const char __user *oldname,
- int newdfd, const char __user *newname)
+SYSCALL_DEFINE3(symlinkat, const char __user *, oldname,
+ int, newdfd, const char __user *, newname)
{
- int error = 0;
- char * from;
- char * to;
+ int error;
+ char *from;
+ char *to;
struct dentry *dentry;
struct nameidata nd;
from = getname(oldname);
- if(IS_ERR(from))
+ if (IS_ERR(from))
return PTR_ERR(from);
- to = getname(newname);
- error = PTR_ERR(to);
- if (IS_ERR(to))
- goto out_putname;
- error = do_path_lookup(newdfd, to, LOOKUP_PARENT, &nd);
+ error = user_path_parent(newdfd, newname, &nd, &to);
if (error)
- goto out;
+ goto out_putname;
+
dentry = lookup_create(&nd, 0);
error = PTR_ERR(dentry);
if (IS_ERR(dentry))
goto out_unlock;
- error = vfs_symlink(nd.path.dentry->d_inode, dentry, from, S_IALLUGO);
+ error = mnt_want_write(nd.path.mnt);
+ if (error)
+ goto out_dput;
+ error = security_path_symlink(&nd.path, dentry, from);
+ if (error)
+ goto out_drop_write;
+ error = vfs_symlink(nd.path.dentry->d_inode, dentry, from);
+out_drop_write:
+ mnt_drop_write(nd.path.mnt);
+out_dput:
dput(dentry);
out_unlock:
mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
path_put(&nd.path);
-out:
putname(to);
out_putname:
putname(from);
return error;
}
-asmlinkage long sys_symlink(const char __user *oldname, const char __user *newname)
+SYSCALL_DEFINE2(symlink, const char __user *, oldname, const char __user *, newname)
{
return sys_symlinkat(oldname, AT_FDCWD, newname);
}
if (!inode)
return -ENOENT;
- error = may_create(dir, new_dentry, NULL);
+ error = may_create(dir, new_dentry);
if (error)
return error;
*/
if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
return -EPERM;
- if (!dir->i_op || !dir->i_op->link)
+ if (!dir->i_op->link)
return -EPERM;
- if (S_ISDIR(old_dentry->d_inode->i_mode))
+ if (S_ISDIR(inode->i_mode))
return -EPERM;
error = security_inode_link(old_dentry, dir, new_dentry);
if (error)
return error;
- mutex_lock(&old_dentry->d_inode->i_mutex);
- DQUOT_INIT(dir);
+ mutex_lock(&inode->i_mutex);
+ vfs_dq_init(dir);
error = dir->i_op->link(old_dentry, dir, new_dentry);
- mutex_unlock(&old_dentry->d_inode->i_mutex);
+ mutex_unlock(&inode->i_mutex);
if (!error)
- fsnotify_link(dir, old_dentry->d_inode, new_dentry);
+ fsnotify_link(dir, inode, new_dentry);
return error;
}
* with linux 2.0, and to avoid hard-linking to directories
* and other special files. --ADM
*/
-asmlinkage long sys_linkat(int olddfd, const char __user *oldname,
- int newdfd, const char __user *newname,
- int flags)
+SYSCALL_DEFINE5(linkat, int, olddfd, const char __user *, oldname,
+ int, newdfd, const char __user *, newname, int, flags)
{
struct dentry *new_dentry;
- struct nameidata nd, old_nd;
+ struct nameidata nd;
+ struct path old_path;
int error;
- char * to;
+ char *to;
if ((flags & ~AT_SYMLINK_FOLLOW) != 0)
return -EINVAL;
- to = getname(newname);
- if (IS_ERR(to))
- return PTR_ERR(to);
-
- error = __user_walk_fd(olddfd, oldname,
- flags & AT_SYMLINK_FOLLOW ? LOOKUP_FOLLOW : 0,
- &old_nd);
+ error = user_path_at(olddfd, oldname,
+ flags & AT_SYMLINK_FOLLOW ? LOOKUP_FOLLOW : 0,
+ &old_path);
if (error)
- goto exit;
- error = do_path_lookup(newdfd, to, LOOKUP_PARENT, &nd);
+ return error;
+
+ error = user_path_parent(newdfd, newname, &nd, &to);
if (error)
goto out;
error = -EXDEV;
- if (old_nd.path.mnt != nd.path.mnt)
+ if (old_path.mnt != nd.path.mnt)
goto out_release;
new_dentry = lookup_create(&nd, 0);
error = PTR_ERR(new_dentry);
if (IS_ERR(new_dentry))
goto out_unlock;
- error = vfs_link(old_nd.path.dentry, nd.path.dentry->d_inode, new_dentry);
+ error = mnt_want_write(nd.path.mnt);
+ if (error)
+ goto out_dput;
+ error = security_path_link(old_path.dentry, &nd.path, new_dentry);
+ if (error)
+ goto out_drop_write;
+ error = vfs_link(old_path.dentry, nd.path.dentry->d_inode, new_dentry);
+out_drop_write:
+ mnt_drop_write(nd.path.mnt);
+out_dput:
dput(new_dentry);
out_unlock:
mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
out_release:
path_put(&nd.path);
-out:
- path_put(&old_nd.path);
-exit:
putname(to);
+out:
+ path_put(&old_path);
return error;
}
-asmlinkage long sys_link(const char __user *oldname, const char __user *newname)
+SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname)
{
return sys_linkat(AT_FDCWD, oldname, AT_FDCWD, newname, 0);
}
* we'll need to flip '..'.
*/
if (new_dir != old_dir) {
- error = permission(old_dentry->d_inode, MAY_WRITE, NULL);
+ error = inode_permission(old_dentry->d_inode, MAY_WRITE);
if (error)
return error;
}
return error;
if (!new_dentry->d_inode)
- error = may_create(new_dir, new_dentry, NULL);
+ error = may_create(new_dir, new_dentry);
else
error = may_delete(new_dir, new_dentry, is_dir);
if (error)
return error;
- if (!old_dir->i_op || !old_dir->i_op->rename)
+ if (!old_dir->i_op->rename)
return -EPERM;
- DQUOT_INIT(old_dir);
- DQUOT_INIT(new_dir);
+ vfs_dq_init(old_dir);
+ vfs_dq_init(new_dir);
old_name = fsnotify_oldname_init(old_dentry->d_name.name);
return error;
}
-static int do_rename(int olddfd, const char *oldname,
- int newdfd, const char *newname)
+SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname,
+ int, newdfd, const char __user *, newname)
{
- int error = 0;
- struct dentry * old_dir, * new_dir;
- struct dentry * old_dentry, *new_dentry;
- struct dentry * trap;
+ struct dentry *old_dir, *new_dir;
+ struct dentry *old_dentry, *new_dentry;
+ struct dentry *trap;
struct nameidata oldnd, newnd;
+ char *from;
+ char *to;
+ int error;
- error = do_path_lookup(olddfd, oldname, LOOKUP_PARENT, &oldnd);
+ error = user_path_parent(olddfd, oldname, &oldnd, &from);
if (error)
goto exit;
- error = do_path_lookup(newdfd, newname, LOOKUP_PARENT, &newnd);
+ error = user_path_parent(newdfd, newname, &newnd, &to);
if (error)
goto exit1;
if (newnd.last_type != LAST_NORM)
goto exit2;
+ oldnd.flags &= ~LOOKUP_PARENT;
+ newnd.flags &= ~LOOKUP_PARENT;
+ newnd.flags |= LOOKUP_RENAME_TARGET;
+
trap = lock_rename(new_dir, old_dir);
old_dentry = lookup_hash(&oldnd);
if (new_dentry == trap)
goto exit5;
+ error = mnt_want_write(oldnd.path.mnt);
+ if (error)
+ goto exit5;
+ error = security_path_rename(&oldnd.path, old_dentry,
+ &newnd.path, new_dentry);
+ if (error)
+ goto exit6;
error = vfs_rename(old_dir->d_inode, old_dentry,
new_dir->d_inode, new_dentry);
+exit6:
+ mnt_drop_write(oldnd.path.mnt);
exit5:
dput(new_dentry);
exit4:
unlock_rename(new_dir, old_dir);
exit2:
path_put(&newnd.path);
+ putname(to);
exit1:
path_put(&oldnd.path);
-exit:
- return error;
-}
-
-asmlinkage long sys_renameat(int olddfd, const char __user *oldname,
- int newdfd, const char __user *newname)
-{
- int error;
- char * from;
- char * to;
-
- from = getname(oldname);
- if(IS_ERR(from))
- return PTR_ERR(from);
- to = getname(newname);
- error = PTR_ERR(to);
- if (!IS_ERR(to)) {
- error = do_rename(olddfd, from, newdfd, to);
- putname(to);
- }
putname(from);
+exit:
return error;
}
-asmlinkage long sys_rename(const char __user *oldname, const char __user *newname)
+SYSCALL_DEFINE2(rename, const char __user *, oldname, const char __user *, newname)
{
return sys_renameat(AT_FDCWD, oldname, AT_FDCWD, newname);
}
{
struct nameidata nd;
void *cookie;
+ int res;
nd.depth = 0;
cookie = dentry->d_inode->i_op->follow_link(dentry, &nd);
- if (!IS_ERR(cookie)) {
- int res = vfs_readlink(dentry, buffer, buflen, nd_get_link(&nd));
- if (dentry->d_inode->i_op->put_link)
- dentry->d_inode->i_op->put_link(dentry, &nd, cookie);
- cookie = ERR_PTR(res);
- }
- return PTR_ERR(cookie);
+ if (IS_ERR(cookie))
+ return PTR_ERR(cookie);
+
+ res = vfs_readlink(dentry, buffer, buflen, nd_get_link(&nd));
+ if (dentry->d_inode->i_op->put_link)
+ dentry->d_inode->i_op->put_link(dentry, &nd, cookie);
+ return res;
}
int vfs_follow_link(struct nameidata *nd, const char *link)
/* get the link contents into pagecache */
static char *page_getlink(struct dentry * dentry, struct page **ppage)
{
- struct page * page;
+ char *kaddr;
+ struct page *page;
struct address_space *mapping = dentry->d_inode->i_mapping;
page = read_mapping_page(mapping, 0, NULL);
if (IS_ERR(page))
return (char*)page;
*ppage = page;
- return kmap(page);
+ kaddr = kmap(page);
+ nd_terminate_link(kaddr, dentry->d_inode->i_size, PAGE_SIZE - 1);
+ return kaddr;
}
int page_readlink(struct dentry *dentry, char __user *buffer, int buflen)
}
}
-int __page_symlink(struct inode *inode, const char *symname, int len,
- gfp_t gfp_mask)
+/*
+ * The nofs argument instructs pagecache_write_begin to pass AOP_FLAG_NOFS
+ */
+int __page_symlink(struct inode *inode, const char *symname, int len, int nofs)
{
struct address_space *mapping = inode->i_mapping;
struct page *page;
void *fsdata;
int err;
char *kaddr;
+ unsigned int flags = AOP_FLAG_UNINTERRUPTIBLE;
+ if (nofs)
+ flags |= AOP_FLAG_NOFS;
retry:
err = pagecache_write_begin(NULL, mapping, 0, len-1,
- AOP_FLAG_UNINTERRUPTIBLE, &page, &fsdata);
+ flags, &page, &fsdata);
if (err)
goto fail;
int page_symlink(struct inode *inode, const char *symname, int len)
{
return __page_symlink(inode, symname, len,
- mapping_gfp_mask(inode->i_mapping));
+ !(mapping_gfp_mask(inode->i_mapping) & __GFP_FS));
}
const struct inode_operations page_symlink_inode_operations = {
.put_link = page_put_link,
};
-EXPORT_SYMBOL(__user_walk);
-EXPORT_SYMBOL(__user_walk_fd);
+EXPORT_SYMBOL(user_path_at);
EXPORT_SYMBOL(follow_down);
EXPORT_SYMBOL(follow_up);
EXPORT_SYMBOL(get_write_access); /* binfmt_aout */
EXPORT_SYMBOL(page_symlink);
EXPORT_SYMBOL(page_symlink_inode_operations);
EXPORT_SYMBOL(path_lookup);
+EXPORT_SYMBOL(kern_path);
EXPORT_SYMBOL(vfs_path_lookup);
-EXPORT_SYMBOL(permission);
-EXPORT_SYMBOL(vfs_permission);
+EXPORT_SYMBOL(inode_permission);
EXPORT_SYMBOL(file_permission);
EXPORT_SYMBOL(unlock_rename);
EXPORT_SYMBOL(vfs_create);
Code Review / linux-2.6.git / blobdiff